PLATFORM
The solver in depth, and the proof.
ThrustLab couples the battery, ESC, motor, and propeller into one converged operating point, over a curated catalog of thousands of motors, propellers, and batteries, or parts you build yourself and export to CAD. This page shows how that solve works, and how it's checked, case by case, against measured wind-tunnel data.
Coupled solver
One power path, every loss in the loop.
A calculator chains four independent lookups. ThrustLab solves the whole bus at once: the pack's loaded voltage sets the motor's operating point, the motor loads the propeller, and the propeller's draw feeds back to the pack. Everything converges together, so a change anywhere propagates everywhere.
Schematic of the modeled loss mechanisms at each stage. The actual power split depends on your motor, propeller, pack, and operating point.
What it models
The physics behind the operating point
ThrustLab solves the whole powertrain as one nonlinear system rather than a chain of independent lookup tables. These are the effects it captures.
Internal-resistance droop under load, computed per cell, so the pack voltage the motor sees is the real loaded voltage rather than the nameplate.
Switching and conduction losses, with a choice of six-step or field-oriented commutation and adjustable timing advance.
Field weakening, six-step modulation, and a torque-balance current solve, so RPM and current land where the magnetics actually put them.
Battery, ESC, motor, and propeller solved together to a converged point, so nothing is computed in isolation.
Winding and magnet temperatures from a size-scaled model with slipstream or cowling cooling, evaluated over the flight duration instead of an infinite hover.
Per-cell core and case heating across the pack, coupled back into discharge so hot cells sag harder.
Blade-tip Mach is tracked and flagged when a tip approaches the compressible regime.
Build your own
Scan or design a blade, then export the solid to CAD.
Scan a real propeller from a photo, generate one from a design point, or draw the blade station by station. The swept 3D body you build goes straight to STEP, IGES, or STL for manufacturing, and it's the same lofted geometry the solver runs.
A representative generated 3-blade racing-prop design, lofted from its per-station airfoil sections. It shows geometry only, not performance.
Validation
The predictions land on the measured data.
Every point is one of 2,659 measured cases from the UIUC propeller wind-tunnel database. The tighter the cloud hugs the 1:1 line, the closer ThrustLab's blade-element-momentum prediction sits to reality. Thrust is on the left, power on the right.
Predicted vs. measured thrust (C_T) and power (C_P) coefficients for the ThrustLab propeller solver over the UIUC database (Selig et al.), N = 2,659. The scatter is a representative sample of the full set; R² and MAE are computed across all 2,659 cases. Engineering estimates, not certified data.
Across the envelope
One propeller, every operating point.
Thrust and power coefficients for the APC 12x10E as advance ratio sweeps from hover toward the prop's zero-thrust point. The copper line is ThrustLab's prediction; the dots are the measured wind-tunnel data it's checked against. This prop is one of the 17 APC blades, 12 to 21 inches, in the validation set.
APC 12x10E at 5,019 RPM, ThrustLab propeller solver vs. UIUC measured data. Engineering estimates, not certified data.
Methodology
Physics first, coefficients in the solver.
The propeller solver runs blade-element-momentum theory over the real blade geometry, then is checked against measured thrust and power from the UIUC propeller wind-tunnel database. The methodology is open about its scope; the fitted coefficients stay inside the solver. Results are engineering estimates, not certified data, so always bench-test before committing a real build.
Build it in the solver before you build it in metal
Free to start. Upgrade when you need dynamic missions, multi-axis sweeps, or CAD export.